NM_003000.3:c.481G>A

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 4P and 1B. PM1PM2BP4

The NM_003000.3(SDHB):​c.481G>A​(p.Asp161Asn) variant causes a missense change. The variant allele was found at a frequency of 0.00000274 in 1,461,534 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. D161V) has been classified as Uncertain significance.

Frequency

Genomes: not found (cov: 33)
Exomes 𝑓: 0.0000027 ( 0 hom. )

Consequence

SDHB
NM_003000.3 missense

Scores

9
10

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 5.68

Publications

0 publications found
Variant links:
Genes affected
SDHB (HGNC:10681): (succinate dehydrogenase complex iron sulfur subunit B) This tumor suppressor gene encodes the iron-sulfur protein subunit of the succinate dehydrogenase (SDH) enzyme complex which plays a critical role in mitochondria. The SDH enzyme complex is composed of four nuclear-encoded subunits. This enzyme complex converts succinate to fumarate which releases electrons as part of the citric acid cycle, and the enzyme complex additionally provides an attachment site for released electrons to be transferred to the oxidative phosphorylation pathway. The SDH enzyme complex plays a role in oxygen-related gene regulation through its conversion of succinate, which is an oxygen sensor that stabilizes the hypoxia-inducible factor 1 (HIF1) transcription factor. Sporadic and familial mutations in this gene result in paragangliomas, pheochromocytoma, and gastrointestinal stromal tumors, supporting a link between mitochondrial dysfunction and tumorigenesis. Mutations in this gene are also implicated in nuclear type 4 mitochondrial complex II deficiency. [provided by RefSeq, Jun 2022]
SDHB Gene-Disease associations (from GenCC):
  • Carney-Stratakis syndrome
    Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Genomics England PanelApp, G2P, Orphanet
  • gastrointestinal stromal tumor
    Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Genomics England PanelApp, G2P, Labcorp Genetics (formerly Invitae)
  • hereditary pheochromocytoma-paraganglioma
    Inheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: ClinGen, Orphanet
  • pheochromocytoma
    Inheritance: AD Classification: DEFINITIVE Submitted by: G2P
  • pheochromocytoma/paraganglioma syndrome 4
    Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Genomics England PanelApp, Ambry Genetics, Labcorp Genetics (formerly Invitae)
  • mitochondrial disease
    Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
  • renal cell carcinoma
    Inheritance: AD Classification: STRONG Submitted by: Genomics England PanelApp
  • mitochondrial complex 2 deficiency, nuclear type 4
    Inheritance: AR Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
  • Cowden disease
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • mitochondrial complex II deficiency
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 3 ACMG points.

PM1
In a region_of_interest Interaction with SDHAF1 (size 72) in uniprot entity SDHB_HUMAN there are 37 pathogenic changes around while only 2 benign (95%) in NM_003000.3
PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (MetaRNN=0.30127883).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
SDHBNM_003000.3 linkc.481G>A p.Asp161Asn missense_variant Exon 5 of 8 ENST00000375499.8 NP_002991.2 P21912
SDHBNM_001407361.1 linkc.427G>A p.Asp143Asn missense_variant Exon 5 of 8 NP_001394290.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
SDHBENST00000375499.8 linkc.481G>A p.Asp161Asn missense_variant Exon 5 of 8 1 NM_003000.3 ENSP00000364649.3 P21912

Frequencies

GnomAD3 genomes
Cov.:
33
GnomAD2 exomes
AF:
0.00000398
AC:
1
AN:
251364
AF XY:
0.00
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000880
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000274
AC:
4
AN:
1461534
Hom.:
0
Cov.:
29
AF XY:
0.00000275
AC XY:
2
AN XY:
727108
show subpopulations
⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.
African (AFR)
AF:
0.00
AC:
0
AN:
33474
American (AMR)
AF:
0.00
AC:
0
AN:
44722
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26130
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39698
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86250
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53368
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00000360
AC:
4
AN:
1111734
Other (OTH)
AF:
0.00
AC:
0
AN:
60390
⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.00117289), which strongly suggests a high chance of mosaicism in these individuals.
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.388
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
Cov.:
33

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:2
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Pheochromocytoma;C0238198:Gastrointestinal stromal tumor;C1861848:Pheochromocytoma/paraganglioma syndrome 4 Uncertain:1
May 15, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces aspartic acid, which is acidic and polar, with asparagine, which is neutral and polar, at codon 161 of the SDHB protein (p.Asp161Asn). This variant is present in population databases (no rsID available, gnomAD 0.0009%). This variant has not been reported in the literature in individuals affected with SDHB-related conditions. ClinVar contains an entry for this variant (Variation ID: 528726). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt SDHB protein function with a negative predictive value of 80%. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Gastrointestinal stromal tumor Uncertain:1
Jul 11, 2023
Baylor Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.080
BayesDel_addAF
Uncertain
0.062
T
BayesDel_noAF
Benign
-0.15
CADD
Benign
22
DANN
Uncertain
1.0
DEOGEN2
Benign
0.26
T;.;T
Eigen
Benign
0.026
Eigen_PC
Uncertain
0.23
FATHMM_MKL
Uncertain
0.95
D
LIST_S2
Uncertain
0.97
D;D;D
M_CAP
Uncertain
0.14
D
MetaRNN
Benign
0.30
T;T;T
MetaSVM
Uncertain
0.45
D
MutationAssessor
Benign
0.54
N;.;.
PhyloP100
5.7
PrimateAI
Uncertain
0.59
T
PROVEAN
Benign
-0.020
N;.;.
REVEL
Uncertain
0.37
Sift
Benign
0.39
T;.;.
Sift4G
Benign
0.56
T;T;T
Polyphen
0.0
B;.;.
Vest4
0.68
MutPred
0.33
Loss of ubiquitination at K159 (P = 0.0456);.;.;
MVP
0.93
MPC
0.16
ClinPred
0.41
T
GERP RS
5.9
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.10
gMVP
0.75
Mutation Taster
=36/64
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.0
Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

Other links and lift over

dbSNP: rs1553177682; hg19: chr1-17354303; API